repsim

A Natural Selection Sim

Available for FREE on  iPad and  macOS!
Or play for FREE in your Chrome browser at  itch.io!


What is a natural selection sim?

Watch simulated life evolve right before your eyes!  

Natural selection weeds out replicators (reps) that can't compete! Selectively breed or let them fend for themselves to see what forms emerge. Feed them, cull them, and toss them into each other. Place objects in their tank that you can drag and throw around. There is even a virus that can take over if the tank becomes too crowded!

Repsim is not only a fun way to explore natural selection, it's also great as an educational tool for science teachers and students. 


Jam Out! 

 Repsim features all-original musical tracks. Each track is meant to loop endlessly and set a different mood. Users can skip through a range of tracks as they play, from calming atmospheric music to wacky surf songs. New tracks will be included with every update!

Use the contact form below to report bugs, or request new features, give feedback, and receive support!

Click here to view the Repsim privacy policy.

The Simulation

In Repsim, natural selection takes place within a tank of randomly generated replicators called “reps”. Reps are built out of five segment types, distinguished by color:

Red: Attack & feed when they hit another rep
Green: Generate health every second
Yellow: Provide movement every 1.25 seconds
Blue: Heal damaged segments
Purple: Allow a rep to breed (reps without purple segments clone themselves)

Before a new tank sim is started, the properties of each segment type can be adjusted. For example, you could make red segments do more or less damage. When you’re done adjusting the sim settings, it’s time to fill the tank!

When the simulation starts, a tank is filled with reps. Each rep has a genome that determines the order and orientation of its segments. When replication (self-cloning) or reproduction (breeding) happens, genetic material is passed on to the next generation with a small chance for mutation. When reps with purple parts touch another rep, they combine the other's genome with their own to make a child!

Users can save reps in one tank and spawn them in another with new settings. This allows users to see how the same rep behaves and evolves in multiple environments.

 

This is just a taste of what you'll see once your sim tank is up and running. There's even more left to discover in the in-app tutorial!

Use the contact form below to report bugs, or request new features, give feedback, and receive support!

Click here to view the Repsim privacy policy.

Possible upcoming features

I have no timeline for these additional features, and some may never come to pass. This is just a spitball list... thinking "out loud".

- Other viruses (sticky virus, disable replication virus, among others)
- PDF manual and curriculum to be available for download here
- Day/Night cycle: make the amount of HP produced by green segments depend on a day/night cycle
- Adjustable Object Properties for sphere cube and divider (mass, size, stickiness, repulsion, damage, healing)
- Variable sized segments (with correspondingly varied segment strengths/properties)
- Variable tank dimensions
- Share reps with others and long term rep saves

Known bugs (to be fixed in the next update)

- *Not actually a bug (but will mention in in-app documentation): reps moving without yellow segments - this is due to overlapping
     segments attempting to pull themselves apart but not being able to. This struggle generates motion that does not cost HP.

- Letterboxing on macOS in fullscreen mode (black bars at the top and bottom of the screen)



Use the contact form below to report bugs, or request new features, give feedback, and receive support!

Click here to view the Repsim privacy policy.